The Affordable Care Act provides subsidies to help people buy private insurance coverage through newly formed insurance exchanges. The subsidies are pegged to household income, so the poorest people get the biggest subsidies. Federal assistance disappears once income reaches 400 percent of the federal poverty line.

Because subsidies decrease as income rises, Heritage argued, some employees will pass up better jobs so they can keep collecting healthcare subsidies.

"Under the Affordable Care Act’s system of subsidies, as an individual makes more money, they are rewarded by losing subsidies," Heritage said. "This creates a calculation that each person must make—whether or not to strive to increase their personal household income through working more or getting a better job, or choosing to stay in a similar place in life in order to keep the benefits."